Drill-bit clutch.



1. w.l ROBY. I

DRILL BIT CLUTCH. APPLLcATloN 'FILED ZAPR. 22. 1914.

. T all whom t may concern JOHN w. ROB'Y, or HnivrivioN, OKLAHOMA.

DRILL-Brr CLUTCH.

Specification of Letters Patent.

patented June s, i915.

Application flied April a2, 1914. serial no. 833,760.

Be it known that I, JOHN W. Rorga citizen of thelUnited States, residingat Ilaminon,

l in the county of 'Roger Mills, State of Okla- I honra, have inventedcertain new and useful Improvements in Drill-Bit Clutches; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

This invention relates to the art of drilling wells and has specialreference to a drill bit clutch designed to act in conjunction with thecasing in drilling a bored well.

' The principal ob] ect of the invention is to vprovide an improved formof bit. clutch which may vbe used in connectionwith the casing of a wellto drill the well through a rotary boring, operation, said clutch bein/garranged to be inserted or removed from the lower end ofthe casing bysuitable tools and yet to be connected to said easing so as to rotatetherewith during the boring voperation. 1 I

With the above and other objects view the invention-consists in generalof certain novel details ofconstruction and combination of partshereinafter fully described, illustrated in the accompanying drawings,

f and 'specifically claimed.

In the accompanying drawings, like characters of reference indicate likeparts in the several views, and :-Figure 1 is a vertical section througha bored well showing the tool'in position in the bottom thereof. Fig.

2 is a section on the line 2-2 of Fig. 1. Fig.

iso'

3 is a-section on the line 3--3 of Fi 1'.- Fig..4 is a perspective viewof the c utch removed from the well. Fig. 5 is a section through thevwell casing showing the clutch and bit being lowered through saidcasing. Fig. 6 is a view similar to Fig. 5 but'showing the -tool usedfor the removal of thev In the drawings accompanying this inventionthere is disclosed the ordinary tubular well casing 10 but the lower endof this well casing is threaded exteriorly as at 11 and on this threadedlower end is screwed a coupling 12. To this coupling is attached aboring .member 13 having serrations 14 on its llower-end, it'beingunderstood that the member 12 is of'suiicient: length so that the lowerend of the casing 10 is spaced from the upper endvof the member 13. Thiscougpling 1-2 is provided on its interior, be-

tween tlie threaded ortions thereof with grooves 15.

The bit clutch proper consists of a circular member 16 provided withgrooves 17 on its outer surface corresponding to the number of grooves15 in the member 12. Leading inward from these grooves 15 are pinreceiving openings 18 wherein fit pins 19 carried by pawl members 20.Between the inner sidesof the pawl members 20 and the bottoms of thegrooves 17 are located spiral springs 21 which normally urge said paWlmembers outward. The upper ends of these pawl members are provided withresilient `estensione 22' for purposes hereinafter to be y described. p

The member\` 16 is hollow and isthreaded at its lower end for thereception of the shank 23 of-a drill bit 211, the drill bit beingprovided with the usual' washer 25 and packing basket 26. /Theinember 16is ofsuch size as to t snugly inthe casing 10 so that when this memberpasses down into the casing and arrives at the member 12 the springs areenabled to force the pawls 2O outward thus" engaging them inthe grooves15 so that when the casing is rotated the drill bit may be rotatedtherewith. In order to lower this member'and also to assist inforcing-the pawls outward thespring fingers 22 are separated slightly,afterthe member has been inserted in the casing, and a suitable pipesection is inserted between the spring ngers so as to enable them togrip said member. The 'lowering ropeisthen attached to this member andthe clutch allowed to pass down the casing until the member 12 isreached.

When this is 'reached thepawls spring outward. Then, upon drawing upwardon the lowering cable, the shoulders 26', formed between the bodies ofthe pawls and the resilient extensions thereon',serve to prevent theAagainst vthe bottom ofthe pipe 10 while the lll() dinally eXtendmgrooves in said coupling.

bulldog itself engages' inside of the member 16 thus enabling thecable',when drawn upward, to engage the member 1'6 'and thereby remove the bitfrom the Well.

There has thus been' rovided av simple and efficient device of thedescribed and of the character-specified.

It will bef; obvious that many minorl changes maybe" made in the formand construction of -this'device vvlthout de arting from thematerial'principles "thereo It is not thereforevdesired to conne' theinven 4 tion ,to the exactlorm hereinshow-n and Idescribed, but wishedto yinclude all such as come properlyjw-ithin the scope' claimed. Havingthus 1escribed the invention, what l. lvIn a Vdevice-'of theVkind:described, the combinationwithlfafwell'easing5 of a coupling ontle'lower end of'said-'well casing, an extension?"screwed'nto saidcoupling, said coupling being provided 'withy longituing member slida lethrough said-casing and provided `with pawls adapted lto engage the 2.ina device of-,ath'evkin 'f'desciibed the combination with-.2a.co'plingmember provided with longitudinally-@neming grooves,

grooves'iand ,a bit carryof a bit carrying member provided withlongitudinally extending grooves corresponding in number to the grooves'of said coupling, strips mounted for radial' movement in said grooves,springs normally urging 'said strips outward, and resilient extensionson the upper ends of said strips, said.v extensions being inclinedinwardly.-

3. In a device of the kind described, a

coupling member provided with longitudinally extendingv groovesintermediate the ends, a bitcarrying memberprovided with longitudinallyextending grooves having radial pin receiving openings Vextendinginwardly therefrom, strips constituting paWls and provided withpins'entering said openings, Said paw'ls being received-in said grooves,springs surrounding said pins and normally urging said pawls outwardly,and

